Consolidated Statements of Changes in Stockholders Equity (Unaudited) (USD $) In Thousands, unless otherwise specified	Total	Preferred stock	Common stock	Retained earnings	Accumulated other comprehensive income
Beginning Balance at Dec. 31, 2011	$ 771,020	$ 50,000	$ 266,842	$ 435,144	$ 19,034
Comprehensive income:
Net income	25,224	0	0	25,224	0
Other comprehensive income, net of tax	(769)	0	0	0	(769)
Common stock transactions:
Common shares purchased and retired 25,677 and 17,981 in 2013 and 2012 respectively	(257)	0	(257)	0	0
Common shares issued 26,096 and 23,973 in 2013 and 2012 respectively	0	0	0	0	0
Non-vested common shares issued 108,873 and 122,912 in 2013 and 2012 respectively	0	0	0	0	0
10,318 and 3,193 non-vested common shares forfeited in 2013 and 2012 respectively	0	0	0	0	0
446,404 and 118,865 stock options exercised, net of 150,290 and 39,667 shares tendered in payment of option price and income tax withholding amounts in 2013 and 2012 respectively	1,263	0	1,263	0	0
Tax benefit of stock-based compensation	126	0	126	0	0
Stock-based compensation expense	1,724	0	1,724	0	0
Cash dividends declared:
Common ($.13) and ($0.24) per share in 2013 and 2012 repectively	(10,290)	0	0	(10,290)	0
Preferred (6.75%) per share in 2012	(1,706)	0	0	(1,706)	0
Ending Balance at Jun. 30, 2012	786,335	50,000	269,698	448,372	18,265
Beginning Balance at Dec. 31, 2012	751,186	0	271,335	463,860	15,991
Comprehensive income:
Net income	41,549	0	0	41,549	0
Other comprehensive income, net of tax	(25,030)	0	0	0	(25,030)
Common stock transactions:
Common shares purchased and retired 25,677 and 17,981 in 2013 and 2012 respectively	(448)	0	(448)	0	0
Common shares issued 26,096 and 23,973 in 2013 and 2012 respectively	0	0	0	0	0
Non-vested common shares issued 108,873 and 122,912 in 2013 and 2012 respectively	0	0	0	0	0
10,318 and 3,193 non-vested common shares forfeited in 2013 and 2012 respectively	0	0	0	0	0
446,404 and 118,865 stock options exercised, net of 150,290 and 39,667 shares tendered in payment of option price and income tax withholding amounts in 2013 and 2012 respectively	5,799	0	5,799	0	0
Tax benefit of stock-based compensation	524	0	524	0	0
Stock-based compensation expense	2,022	0	2,022	0	0
Cash dividends declared:
Common ($.13) and ($0.24) per share in 2013 and 2012 repectively	(5,648)	0	0	(5,648)	0
Ending Balance at Jun. 30, 2013	$ 769,954	$ 0	$ 279,232	$ 499,761	$ (9,039)